Increasing public environmental awareness and concern about the consequences of atmospheric pollution has stimulated determined efforts to find an effective and economical way to rid effluent gases to industrial operations and electric power generating plants of their contaminant burdens. A large number and variety of systems, devices and methods have been proposed in response to this demand and some have been widely used. The apparatus claimed in the above-identified patent application, however, stands out as clearly the most effective and efficient means for this purpose. It also holds an economic advantage over prior art devices, initial cost comparing favorably with that of alternative apparatus in general use and operating and maintenance total cost being relatively very low.